Lineman&#39;s shoe.



H. Ey MARSHALL.

LINEMANS SHOE.

APPLICATION FILED D504.

Patented May 30, 1916.

UNITED sTATEs PATENT onerosi E. MARSHALL, OF HIGHLAND PARK, MICHIGAN.

LINEMANS SHOE.

Specification of Letters Patent.

Patented May 30, l.

Application tiled December 4, i915, Serial No. 84,949.

To all whom t may concern.'

Be it known that lf, HARRY E. MARSHALL, e. citizen of the United States,residing at 'fhland Parli, count)T of Wla'yne, State of lu. Michigan,have invented a certain new and useful Improvement in Linemens Shoes,und declare the following to be a full, clear, and exact description ofthe same, such as will enable .or-hers skilled in the art to which i;pertains to make end use the same, relie-1T- ence being had to theaccompanying drowi ings, which form a part lof this speelication.

This

invention. relates to shoes for linenien employed in repairingr orWorking on lines verrvingg electric current.

"The obje-:ln of the invention is en imuzlatA ing shoe wl ich isconstructed to afford o. very high resistance to the passage ofeleoourwfnt as for instance, :i resistance. wlnoli will prevent thepsssl'ige of a Current il folie and upward.

T noe is constructed in such e Way so five e, visible warning when Wornto e. point where its resistingeflieieney is lowered. The shoe is alsoconstructed in such a way as to prevent the registry of blow-holes inthe rubber insulating medium which might easily 'breek down whensubjected to smaller eurrents than those for which the shoe is tested.

In the dreWings,-Figure l is e Side elevafion of the shoe. Fig. 2 is o.vertical long'tudinal section of the lower port of the oe. 3 front Viewof the .lower prt of the shoe with a half of the saine sectioned y I 0,designates the mp which is eonstiueteil preferably of White rubberhaving high wearing properties. l

.7J is an insulzitingfy sole constructed @refern nbly of brown rubberwhich has a high electrical-resistance eilieienejf.

o represents e number of layers of waterproof rneterialoustructed of acompound made of scrap, such cork. reclaimed ruhber sind like materialswhich are ground up and formed into a. compound which is lighter thansolid rubber and yetwater proof. The idea of these. layers is only toform aI sort of filler material which is win ternroof and yet lighterthan solid rubber.

al represents the fabric on the inside of the sole which lines the.salme.

e designates the heel constructed prefeiw ably of brown rubber.

I It will be noted that the tap extends out in front of the shoe ntthefront so ves to guard as for es possible weer upon the insu loting soleb which is also turned up et the side o the shoe eli the way around esindicated in Fig. l izo afford si'sitehle insulation at the edges.

The upper is constructed of e top portion of waterproof leether whichhas eyelets thut eye mere perforutions, and the whole shoe kept freefrom my metallic. devices whatever. leather sit-ring g used to lace theshoes.

The loo portion of the upper eoinprises "uwer :on .71, which extendscompletely nfil tire shoe and oeoupies the greater elution of the lowerportion., and which elle insulated section. The purpose oi' s e' and toinsulate this poro@ is not only 'lo gela thicker l renee a., this pointbuior the very irnnortunt ,object of avoiding the registry of 'bhw/holesin the rubber as'. 'fer es'possible. luesnuie-h as rubber ea Jily breaksdown when subjected to electric eurrent at points where there areblowlholesit 'is very' i.. portent. that the likelihood of blowholes heeliminated if possible, and if it cannot wholli7 he eliminated, thenprotection be affordod :i geinstserious effects from such blowholes. 'lhere oceonlplishedby vulcanizingr the two layers of rubber of highelectrisel efficiency. nasmuch as the upper serrlion of the lowerportion of the shoe is inotfn dangerous Zone, the twoday sin rangementis not continued clear .to thi lop 5 it makes ehe shoe more flexible andeasier to walk in to have the upper seotion. of the lower portion thinand flexible'. The inside of the upper is provided with a fabric lining1.

l; muy be remarked before explaining how all these verts ere fixedtogether, that the likelihood. of blow-holes allowing the sole to breekdown is also oonsiderebhlmini'- mized by the reason of the vulcanizetionof three loyers rubber compounds, the rubber tap C, of high wearingefficiency rubher, the insulating sole l) of high electrical elli eiencjrubber, and the compound c. which is n filler made of scrap material.All these loyers of rubber and fabric are vulcanized ogether by esuitable mlcenizing process, as for instance. by the use of highpressure sind heY j' furnished by steam under pressure. However, l donot limi myself to any pee ticular way of vulcanizing these various lay.

ers together.

lt is very desirable to guard against inishap in every way possible inpreserving life. Consequently l have found it advantageous to constructmy shoe olE rubber of such color that it is not likely to be mistakenfor other things. For instance, the uppers are constructed of achocolate colored rubber as is also the heel c, while the, tap isconstructed of white rubber compound. lt is especially important thatthe tap and the insulating sole should be constructed of layers of rubber of different colors. To this end the insulating sole is constructedof. a chocolate colored rubber, the tap sole being constructed of whiterubber compound. W'hen the white top wears away and exposes theinsulating sole. a visible warning is immediately given to the user ofthe shoes or his employer that the danger point has been reached andthat either the slice should be repaired or thrown away.

l have found that a shoe constructed in accordance with the abovedescription will stand the test of over 30.000 volts without breakingdown. 'lt is obvious that when linernen are provided with these shoes.al-V most a constant precaution against death is secured, as the use ofthe safety devices is not attendant upon the care of the lineman but onthe contrary this insulating medium con stantly attends him and protectshim in all cases except where he deliberatelyr takes them od.

In the description and claims l speak of rubber having certain specifiedcharacteristics, but it will bc understood that such subn stances arereally rubber compounds and suitable rubber compounds lrnoivn as rubberhaving the specified characteristics can be obtained from anymanufacturerlof commercial rubber. inasmuch as cach inanufacturer variesthese compounds, the ingredients of each arc not given.

Ordinarily electrical transmission lines .carry 20,000 volts more orless and the material in my shoe is designed to resist such electricalcurrents without breaking down.

By the use of such terms as high tension electrical currents or similarexpressions in the claims I means electrical currents substantially ashigh as 0,000 volts.

What I claim is:

1. IA linemans shoe. comprising an up.

per andl a sole, the latter having anouter layer of a rubber compoundhaving high wearing properties and an insulating layer of a rubbercompound constructed for and capable of resisting high tensionelectrical currents.

2. A linemans shoe, comprising an upper and a sole secured thereto.comprising an outer layer of one color and thereabove an electricalinsulating medium calculated to resist vthe passage of relatively heavyvoltage electrical currents, said insulating medium being of a differentcolor so that when the outer layer wears away the danger of wearing awaythe insulating medium is indicated.

3. A linemans shoe, comprising an upper and a sole, the lattercomprising an outer layer of rubber compound of relatively high wearingefficiency and of a specified color, and an ,inner insulating layerconstructed of a rubber compound. of a different color and having arelatively high electrical resistance.

fl. A linemans shoe, having an insulating sole and an upper, the lowerportion of which is constructed of two layers having llat co` incidingcontinuous surfaces which are vulcanized together, and which are eachoit a rubber compound possessing high electrical resistance properties.

5. A. linemans shoe, having` au electric `insulating sole and an upper,the lower section of the lower portion of which is constructed of twolayers or' high elliciency electrical-resistance rubber which arevulca-nized together and the top section o' which lower portion isconstructed of a single layer of rubber having a relatively highelectrical resistance.

6. A linemans shoe, comprising an upperand a sole, the latter having anouter layer of a rubber compound having high wearing properties, aninner insulating layer of a rubber compound constructed for and capableof resisting high tension electrical currents, and a layer inside of theinsulating layer constructed of filler material which is water-proof andlighter than solid rubber compound.

7. A linenians shoe, having a sole and the lower portionvof the upperconstructed of rubber including a complete ensheathing of a rubber layerof relatively high electrical current resisting properties.

8. A linemans shoe, having a sole and the lower portion of the upperconstructed of rubber, some of which is calculated to resist highvoltage currentsthe said Sole v than such first-mentioned layer so thatwhen it wears away the exposure of the inner insulating layer 1sevident.

and which exbafms up at the sides and over- Ries im lapped gmrtions of'ihe tvc@ high eimrw m "www unizwruls i3 inemmzs. shoe, lxmmg a soleproxdei with a Raye? af material capable of re- ;Qing ihr* highresstancf@ currents used in fslfwz'iafa rzmmirfson lines and an upperwhew ms'm" pw'rtm im@ an ensheathng uf mnmix :nimble uf resisting highrabid-Mme zum K f' nf fcz'cal transmission huw. dm mi; Myerswmogencously running iff'ygehei".

la wmmonj: 'whueof sign this speciliration.

H ARY E. MARSHALL.

